Make hashCode a getter and not a method.

runtime/bin/websocket.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /**
  * Web socket status codes used when closing a web socket connection.
  */
 abstract class WebSocketStatus {
   static const int NORMAL_CLOSURE = 1000;
   static const int GOING_AWAY = 1001;
@@ skipping 75 matching lines @@
 
   /**
    * Close the web socket connection. The default value for [status]
    * and [reason] are [:null:].
    */
   close([int status, String reason]);
 
   /**
    * WebSocketConnection is hashable.
    */
-  int hashCode();
+  int get hashCode;
 }
 
 
 /**
  * Client web socket connection.
  */
 abstract class WebSocketClientConnection {
   /**
    * Creates a new web socket client connection based on a HTTP client
    * connection. The HTTP client connection must be freshly opened.
@@ skipping 52 matching lines @@
 
   /**
    * Close the web socket connection. The default value for [status]
    * and [reason] are [:null:].
    */
   close([int status, String reason]);
 
   /**
    * WebSocketClientConnection is hashable.
    */
-  int hashCode();
+  int get hashCode;
 }
 
 
 /**
  * Base class for the events generated by the W3C complient browser
  * API for web sockets.
  */
 abstract class Event { }
 
 /**
@@ skipping 114 matching lines @@
    */
   void send(data);
 }
 
 
 class WebSocketException implements Exception {
   const WebSocketException([String this.message = ""]);
   String toString() => "WebSocketException: $message";
   final String message;
 }